Multiple laminar flow-based rate zonal or isopycnic separation with holographic optical trapping of blood cells and other static components

Abstract

The invention provides a method and apparatus for separating blood into components, may be expanded to include other types of cellular components, and can be combined with holographic optical manipulation or other forms of optical tweezing. One of the exemplary methods includes providing a first flow having a plurality of blood components; providing a second flow; contacting the first flow with the second flow to provide a first separation region; and differentially sedimenting a first blood cellular component of the plurality of blood components into the second flow while concurrently maintaining a second blood cellular component of the plurality of blood components in the first flow. The second flow having the first blood cellular component is then differentially removed from the first flow having the second blood cellular component. Holographic optical traps may also be utilized in conjunction with the various flows to move selected components from one flow to another, as part of or in addition to a separation stage.

1. A method of separating a fluid mixture into constituent, non-motile components, the method comprising:
 providing a substantially laminar first flow having the fluid mixture, the fluid mixture having a plurality of components, the plurality of components having a corresponding plurality of sedimentation rates; 
 providing a substantially laminar second flow; 
 contacting the first flow with the second flow to provide a first separation region, the first flow and the second flow having a substantially non-turbulent interface within the separation region; 
 differentially sedimenting from the first flow a first component of the plurality of components into the second flow to form an enriched second flow and a depleted first flow, while concurrently maintaining a second component of the plurality of components in the first flow, the first component having a first sedimentation rate of the plurality of sedimentation rates and the second component having a second sedimentation rate of the plurality of sedimentation rates, wherein the first sedimentation rate is comparatively greater than the second sedimentation rate; 
 differentially removing the enriched second flow from the depleted first flow; and holographically manipulating the second component in the depleted first flow. 
 
     
     
       2. The method of  claim 1 , wherein the fluid mixture is whole blood, wherein the first component is a plurality of red blood cells and white blood cells, and wherein the second component is a plurality of platelets. 
     
     
       3. The method of  claim 1 , wherein the optical manipulation step further comprises:
 holographically trapping the second component to remove the second component from the depleted first flow. 
 
     
     
       4. The method of  claim 1 , further comprising:
 holographically removing a plurality of contaminants or biological debris from the first flow. 
 
     
     
       5. The method of  claim 1 , further comprising:
 providing a third flow; 
 contacting the depleted first flow with the third flow to provide a second separation region; and 
 holographically trapping the second component and moving the second component from the depleted first flow into the third flow while concurrently maintaining a third component of the plurality of components in the depleted first flow. 
 
     
     
       6. The method of  claim 4 , further comprising: recirculating the depleted first flow to form the second flow.